Double layer cardboard roof



Aug. 2, 1938, P. sATTlG DOUBLE LAYER OARDBOARD ROOF 4Filed Api-i116, 195e 7 mgm' M f a 4 L@ l/ //-'--b Ha.-

f/Z/ f Fig?- Pateniea Aug. 2, 193s "f PATENT y(')FFICE nonoui LAYER cAimmAno noor Philipp saftig, Mannheim, Germany Application April 16,

1936, Serial No. 74,751

ny April 20, `1935 1 Claim.

This invention relates to the production of double-layer cardboard roofs.

The existing method of coveringvroofs with `two layers of standard cardboard united by means of 5 an adhesive is open to serious objections. The rst layer is nailed to the rooi' boarding and immediately afterwards shows all the unevennesses of the boarding inthe form of elevations and depressions in its surface. The second layer is pasted onto the first. but it is impossible to apply an adhesive mass that'can be spread only while hot in a rapid operation byhand without leaving any gaps. Furthermore, in cold weather or a cold draft of air such an ,adhesion solidiesusually before the secondlayer can be pressed on over its entire width. Adhesives that can be applied inl the cold state also involve diilculties. The upper layer to be pressed onto the adhesive is tight and perfectly flat when unrolled and completely covers at rst in a level manner all elevations and depressions, so that' air spaces in the depressions of the first layer are covered also. Owing to the action of the sun, the air in these hollow spaces considerably' expands and enlarges and increases the height of these spaces by separating the two cardboard layers at the points where they are united by the adhesive. 'I'his process constitutes the rst destruction of the rooting. The upper layer increasingly becomes uneven by the formation of cockles.

The invention eliminates the drawbacks mentioned by employing in the production of doublelayer pasted cardboard roofs webs comprising two standard cardboard layers pasted together by factory methods. The layers are staggered relative to one another so as to provide a narrow strip free from adhesive.

The method of laying these webs consists in 40 overlapping the lower layers of two consecutive webs, securing'them by nailing through the nonadhesive strip to the support and uniting the projecting strip of the top layer with the adjacent one by pasting.

'I'he advantages aiox'ded by the invention are obvious.

After the adhesive has been applied in the factory by machinery at a suitable temperature,

the layers are mechanically pressed together, so

that they are intimately united and hollow spaces cannot form between them. A roong of this type cannot be destroyed by solar radiation and, as hollow air-lled spaces between the layers are eliminated, cockles do not appear. Furthlermore, mechanical pasting of the layers in a fac- (Cl. 10S-7) toryl is much more economical than doing this Work by hand on the roof. Factory-made webs of cardboard can be more easily transported than two separate layers and an adhesive mass. The iinished web can be laid in a single operation whilst the laying of two 'separate layers and the pasting thereof on the roof would require three operations and three times the time. Depend-` ence upon the weather is reduced, as interference with the various operations on the roof by rain or snow is avoided.

By way of example, the invention isillustrated in the accompanying drawing, in which Figures 1 and 2 show a web consisting of two layers of standard cardboard, and Figs. 3 and 4 indicate how the webs are laid on the roof.

The two layers a and b are mechanically pasted together and are staggered relative to one another in such manner that the rst layer projects beyond the second and, at the opposite edges, the second beyond the rst to the extent of a narrow strip a1, b1. These strips are free from adhesive. Parallel to the strip a1 a second nonadhesive strip s extends between the two layers which are preferably diagonally displaced to pro- Vide a projecting non-adhesive strip on both the long and cross sides.

The method of laying the mechanically prepared webs is as follows:

The two webs A and B each consist of two layers of standard cardboard pasted together and are superposed so that the lower layer b of the web B lies on the strip b1 of the web A, and both are nailed to the roof boarding c while the strips al, s 'of the web B are raised. Then the strips a1, s of the web B are provided with an adhesive and pasted across and beyond the nailing onto the respective portion of the webA.

The same method is applied to the angularly abutting side of the web.

I claim:-

A roof covering made up of unit sections, each comprising two layers of cardboard or the like of substantially uniform surface area and disposed one upon the other in oset edge relation, whereby a margin of the lower layer projects beyOnd the upper layer at one edge and a similar margin of the upper layei projects beyond the proximate edge of the lower layerat the opposite edge, the contacting faces of the layers being cemented together except for `a marginal area of the lower layer at the edge adjacent the projecting margin of the upper layer, the sections being applied for roong purposes with the uncemented margin of the lower layer resting upon overlle, protect and sed the securing means md tooverlle-andbesecuredtotheupperlayer materially beyond the edle of the upper layer of thepreoeding section, whereby the roo! n s whole presents s double thickness of material throughout its full area and a. third thickness overlying and sealed to the roof covering in both glctions beyond the meeting edges of adjacent PHILIPP SATI'IG. 

